Insert blades must be of the same seat size as the body it should be used on. For each seat size, there is a PREFERRED CHOICE of bodies for a particular insert diameter. Overhang of the insert to the body shall not exceed 0,25mm (0.0098") per side. Higher overhang is possible but will compromise performance, rigidity and efficient chip evacuation. We recommend to always use the closest fit possible, especially when machining long chipping materials.